This invention relates to methods of preventing and treating neurological disorders such as cognitive disorders, and/or neurological disorders related to neuronal apoptosis and/or excitotoxicity, for example Alzheimer""s disease, vascular dementia and age-related dementia as well as head trauma, stroke, spinal cord injury, amyotrophic lateral sclerosis (ALS), Parkinson""s disease, Huntington""s chorea, AIDS-related dementia, peripheral neuropathies and macular degeneration. Such methods comprise the administration to a warm-blooded mammal, such as a human, in need thereof an effective amount of a compound of Formula I or Formula VIII. This invention also relates to the use of a compound of Formula I or Formula VIII for the manufacture of a medicament for the prevention or treatment of the aforementioned disorders.
Alzheimer""s Disease (AD) is the most common form of dementia, affecting approximately 4 million people in the United States alone. AD is a degenerative brain disorder characterized clinically by progressive loss of memory, cognition, reasoning, judgment and emotional stability that gradually leads to profound mental deterioration and ultimately death. AD is a common cause of progressive mental failure (dementia) in aged humans and is believed to represent the fourth most common medical cause of death in the United States. AD has been observed in varied races and ethnic groups worldwide and presents a major present and future public health problem. To date, AD has proven to be incurable. For recent reviews of Alzheimer""s disease see: Edelberg and Wei (1996) Mech Aging and Development 91: 95 and De LaTorre (1994) Neurosci and Biobehavioral Reviews 18:397.
The brains of individuals with AD exhibit neuronal degeneration and characteristic lesions variously referred to as amyloidogenic plaques, vascular amyloid angiopathy, and neurofibrillary tangles. Large numbers of these lesions, particularly amyloidogenic plaques and neurofibrillary tangles, are generally found in several areas of the human brain important for memory and cognitive function in patients with AD. Smaller numbers of these lesions in a more restricted anatomical distribution are found in the brains of most aged humans who do not have clinical AD. Amyloidogenic plaques and vascular amyloid angiopathy also characterize the brains of individuals with Trisomy 21 (Down""s Syndrome) and Hereditary Cerebral Hemorrhage with Amyloidosis of the Dutch-Type (HCHWA-D). At present, a definitive diagnosis of AD usually requires observing the aforementioned lesions in the brain tissue of patients who have died with the disease or, rarely, in small biopsied samples of brain tissue taken during an invasive neurosurgical procedure.
Several lines of evidence indicate that progressive cerebral deposition of particular amyloidogenic proteins, b-amyloid proteins, (b-AP), play a seminal role in the pathogenesis of AD and can precede cognitive symptoms by years or decades. See, Selkoe, (1991) Neuron 6:487. It has been shown that b-AP is released from neuronal cells grown in culture and is present in cerebrospinal fluid (CSF) of both normal individuals and AD patients. See, Seubert et al., (1992) Nature 359:325-327.
A growing amount of research suggests that the pathogenesis of AD is due to impaired vascular delivery of nutrients to the brain. It is suggested that abnormal haemodynamic flow patterns caused by structural deformities of the capillaries leads to dysfunctional cerebral transport of nutrients. The production of plaques and neurofibrillary tangles may develop from hypometabolic abnormalities caused by the impaired cerebromicrovasculature (for a review see: de la Torre (1997) Gerontology 43:26).
Vascular dementia is considered to be the second most common cause of dementia in Europe and the US. In Asia and many developing countries, it is more common than dementia of the Alzheimer""s type. Vascular dementia describes global cognitive decline attributed to the cumulative effects of ischemic vascular disease. Discrete and multiple cognitive skills, including memory, are successively lost as a result of focal cerebrovascular insults. (For a recent review of vascular dementia see: Konno et al (1997) Drugs and Aging, 11:361).
Emopamil is a neuroprotective agent structurally related to the Ca2+ antagonist, verapamil. However, verapamil is only a weak Ca2+ inhibitor in the brain due to limited CNS access. Emopamil, but not verapamil, binds a high affinity site which is present in the endoplasmic reticulum in a number of tissues including brain and liver. Recently, it has been suggested that the emopamil binding protein (EBP) represents an anti-ischemic binding site (Moebius et al, (1993) Mol Pharmacol 43:139). More recently Silve et al have shown that the EBP exhibits xcex948-xcex947 sterol isomerase activity when expressed in yeast (Silve et al (1996) J.Biol. Chem.271:22434). xcex948-xcex947 sterol isomerase is a post squalene enzyme which participates in the conversion of lanosterol to cholesterol.
Surprisingly we have found that the a compound of formula I or formula VIII binds with high affinity to EBP and that a compound of formula I or formula VIII inhibits neuronal cell death in a number of assays of neurodegeneration. The present invention is also based on surprising discovery that a compound of formula I or formula VIII inhibits neuronal apoptosis and excitotoxicity, mechanistically two distinct pathways to neuronal death, and that therefore the compounds of the invention described herein and the pharmaceutically acceptable salts, prodrugs and solvates thereof may be of value in the treatment and/or prevention of neuronal apoptosis and/or excitotoxicity related neurological disorders.
Thus according to the present invention there is provided a method of treating or preventing cognitive disorders, such as Alzheimer""s disease, vascular dementia and age-related dementia, in a warm-blooded mammal, such as man, which comprises administering an effective amount of a compound of Formula I: 
(where R1 is hydrogen or halo; R2 is hydrogen or hydroxy; R3 is hydrogen, hydroxy, halo or PO4; R4 and R5 are either both methyl, are both ethyl or together with the nitrogen atom to which they are attached form a ring selected from pyrrolidine, piperidine or morpholine; R6 is hydrogen or a C1-4 straight or branched alkyl chain and n is 2 or 3) or a pharmaceutically acceptable salt, prodrug or solvate thereof.
Convenient values for R1 are hydrogen or halo, preferably hydrogen or chloro, most preferably hydrogen.
Convenient values for R2 are hydrogen or hydroxy, preferably hydrogen;
Convenient values for R3 are hydrogen, hydroxy, halo or PO4, preferably hydrogen, hydroxy, iodo or PO4, most preferably hydrogen.
Convenient values for R4 and R5 are either both methyl or both ethyl or R4 and R5 together with the nitrogen atom to which they are attached form a ring selected from pyrrolidine, piperidine or morpholine, preferably R4 and R5 are both methyl or together with the nitrogen to which they are attached form a pyrrolidine ring; most preferably R4 and R5 are both methyl.
Convenient values for R6 are hydrogen or a straight or branched C1-4 alkyl chain, preferably hydrogen or isopropyl, most preferably hydrogen.
Convenient values for n are 2 or 3, preferably 2.
According to a further aspect of the present invention there is provided a method of treating or preventing neurological disorders, in a warm-blooded mammal, such as man, which comprises administering an effective amount of a compound of Formula VIII. 
wherein
A and B are selected from: 
xe2x80x83such that when A is of Formula X then B is of Formula IX and when A is of Formula IX then B is of Formula X.
R1 is selected from hydrogen, halo, aryl, carbamoyl, Nxe2x80x94C1-4alkylcarbamoyl or NNxe2x80x94dixe2x80x94C1-4alkylcarbamoyl;
D is selected from C1-4alkylene, C1-4alkenylene or C1-4alkynylene;
R2 is selected from hydrogen, C1-4alkyl or hydroxy;
R3 is selected from hydrogen, hydroxy, halo, PO4, C1-4alkoxy, or a group of the formula:
xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H
xe2x80x83wherein:
E is selected from 
F is selected from 
xe2x80x83or a direct bond;
G is selected from C1-6alkylene, or a direct bond;
H is selected from hydrogen, C1-4alkoxy , aryl; heteroaryl, carbocyclyl, wherein the aryl, heteroaryl or carbocyclyl may be optionally substituted (on an available carbon atom) by up to 3 substituents independently selected from halo, C1-4alkyl, C1-4alkoxy, halo, amino, Nxe2x80x94C1-4alkylamino, NNxe2x80x94dixe2x80x94C1-4alkylamino, aminoC1-4alkyl, or aryl;
R4 and R5 are independently selected from C1-4alkyl, or together with the nitrogen atom to which they are attached form a ring selected from pyrrolidine, piperidine or morpholine;
R6 is selected from hydrogen, C1-4alkyl; C1-4alkoxy, halo, or a ring fused phenyl group fused via carbons 3 and 4 on the phenyl group of formula X;
R7 and R8 are either both hydrogen or when A is of Formula X may be joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94CH2CH2xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively;
R9 is selected from hydrogen or C1-4alkyl;
R10 is selected from hydrogen, C1-4alkyl or halo; and
n is 2 or 3;
or a pharmaceutically acceptable salt, prodrug or solvate thereof.
Compounds used in the methods of the invention can exist in both the cis and trans configuration. Both these configurations are active in the biochemical and cellular assays described below. This is reflected in the values for A and B in Formula VIII.
In this specification the generic term xe2x80x9calkylxe2x80x9d includes both straight-chain and branched-chain alkyl groups. However references to individual alkyl groups such as xe2x80x9cpropylxe2x80x9d are specific for the straight-chain version only and references to individual branched-chain alkyl groups such as xe2x80x9cisopropylxe2x80x9d are specific for the branched-chain version only. An analogous convention applies to other generic terms.
The term xe2x80x9carylxe2x80x9d refers to phenyl or naphthyl.
The term xe2x80x9cheteroarylxe2x80x9d refers to a 5-10 membered aromatic mono or bicyclic ring containing up to 5 heteroatoms independently selected from nitrogen, oxygen or sulphur, linked via ring carbon atoms or ring nitrogen atoms where a bond from a nitrogen is allowed, for example no bond is possible to the nitrogen of a pyridine ring, but a bond is possible through the 1-nitrogen of a pyrazole ring. Examples of 5- or 6-membered heteroaryl ring systems include pyrrole, furan, imidazole, triazole, pyrazine, pyrimidine, pyridazine, pyridine, isoxazole, oxazole, 1,2,4 oxadiazole, isothiazole, thiazole and thiophene. A 9 or 10 membered bicyclic heteroaryl ring system is an aromatic bicyclic ring system comprising a 6-membered ring fused to either a 5 membered ring or another 6 membered ring. Examples of 5/6 and 6/6 bicyclic ring systems include benzofuran, benzimidazole, benzthiophene, benzthiazole, benzisothiazole, benzoxazole, benzisoxazole, indole, pyridoimidazole, pyrimidoimidazole, quinoline, isoquinoline, quinoxaline, quinazoline, phthalazine, cinnoline and naphthyridine.
The term xe2x80x9cheterocyclylxe2x80x9d refers to a 5-10 membered saturated or partially saturated mono or bicyclic ring containing up to 5 heteroatoms selected from nitrogen, oxygen or sulphur linked via ring carbon atoms or ring nitrogen atoms. Examples of xe2x80x98heterocyclylxe2x80x99 include pyrrolinyl, pyrrolidinyl, morpholinyl, piperidinyl, piperazinyl, dihydropyridinyl and dihydropyrimidinyl
The term xe2x80x9ccarbocyclylxe2x80x9d refers to a totally saturated or partially saturated mono, bi or tri cyclic carbon ring. Examples of carbocyclic rings are cyclopentyl, cyclohexyl, bicyclo-octane or adamantyl.
The term xe2x80x9chaloxe2x80x9d refers to fluoro, chloro, bromo or iodo.
The term carbamoyl refers to xe2x80x94C(O)NH2.
Examples of (C1-4)alkyl include methyl, ethyl, propyl, isopropyl, sec-butyl and tert-butyl; examples of (C1-4)alkoxy include methoxy, ethoxy and propoxy; examples of Nxe2x80x94(C1-4)alkylcarbamoyl include methylaminocarbonyl, ethylaminocarbonyl, propylaminocarbonyl, isopropylaminocarbonyl, sec-butylaminocarbonyl and tert-butylaminocarbonyl; examples of NN-di-(C1-4alkyl)carbamoyl include di-methylaminocarbonyl, di-ethylaminocarbonyl and N-ethyl-N-methylaminocarbonyl; Examples of (C1-4)alkenylene include propenylene and 2-butenylene, or 
Examples of (C1-4)alkynylene include: 
Convenient values for R1 are hydrogen, halo, phenyl or NN-di-C1-4alkylcarbamoyl. Preferably hydrogen, chloro, NN-di-ethylcarbamoyl. Most preferably hydrogen.
Convenient values for D are methylene, ethylene, propylene, ethenylene or propenylene. Preferably 2-propenylene or ethylene. Most preferably 2-propenylene.
Convenient values for R2 are hydrogen or C1-4alkyl; Preferably methyl, ethyl or hydrogen. Most preferably hydrogen.
Convenient values for R3 are hydrogen hydroxy, C1-4alkoxy, or a group of the formula: xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H. Preferably hydrogen, hydroxy, methoxy, or a group of the formula:xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H. Most preferably hydrogen, hydroxy or methoxy.
Convenient values for E 
Preferably 
Most preferably 
Convenient values for F are 
or a direct bond;
Preferably a direct bond.
Convenient values for G are ethylene, methylene, propylene, 1,1-dimethylethylene (wherein carbon 1 is attached to F) or a direct bond. Preferably methylene, 1,1-dimethylethylene or a direct bond. Most preferably 1,1 -dimethylethylene or a direct bond.
Convenient values for substituents on an aryl, heteroaryl or carbocyclyl ring at H are C1-4alkyl, halo, amino or xe2x80x94C1-4alkylamino. Preferably C1-4alkyl or amino. Most preferably amino.
Convenient values for R4 and R5 are either independently methyl, ethyl or phenyl, or together with the nitrogen atom to which they are attached form a ring selected from pyrrolidine, piperidine or morpholine. Preferably R4 and R5, each represent methyl, each represent ethyl, R4 is methyl and R5 is phenyl, or R4 and R5 together form a pyrrolidino or piperidino ring. More preferably R4 and R5 each represent methyl, or R4 and R5 together represent a pyrrolidino ring, especially R4 and R5 each represent methyl or together represent a pyrrolidino ring.
Convenient values for R6 are C1-4alkyl, halo. More preferably chloro, fluoro or C1-4alkyl. Preferably chloro, fluoro or ethyl. Most preferably ethyl or fluoro.
Convenient values for R7 and R8 are R7 and R8 each represent hydrogen or R7 and R8 together form an eight membered carbon ring or 7-membered sulphur containing ring as above. Preferably R7 and R8 each represent hydrogen or R7 and R8 together form a 7-membered sulphur containing ring as above. Most preferably R7 and R8 each represent hydrogen.
Convenient values for R9 are hydrogen or ethyl. Most preferably hydrogen.
Convenient values for R10 are hydrogen, methyl, ethyl or halo. Preferably hydrogen or halo. Most preferably chloro.
A preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen; and
D is C1-4alkenylene, preferably 2-propenylene.
A preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is C1-4alkenylene, preferably 2-propenylene.
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 is methyl or ethyl, R5 is methyl, ethyl or phenyl or together R4 and R5 form pyrrolidine or piperidine;
R6 is hydrogen, C1-4alkyl or halo;
R7 and R8 are both hydrogen; and
R9 is hydrogen, methyl or ethyl.
A preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is C1-4alkenylene, preferably 2-propenylene.
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H.
R4 is methyl or ethyl, R5 is methyl, ethyl or phenyl or together R4 and R5 form pyrrolidine or piperidine;
R6 is hydrogen, C1-4alkyl or halo;
R7 and R8 are both hydrogen; and
R9 is hydrogen, methyl or ethyl.
A preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is C1-4alkenylene, preferably 2-propenylene.
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 is methyl or ethyl, R5 is methyl, ethyl or phenyl or together R4 and R5 form pyrrolidine or piperidine;
R6 is hydrogen, C1-4alkyl or halo;
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively; and
R9 is hydrogen, methyl or ethyl.
A preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is C1-4alkenylene, preferably 2-propenylene.
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H.
R4 is methyl or ethyl, R5 is methyl, ethyl or phenyl or together R4 and R5 form pyrrolidine or piperidine;
R6 is hydrogen, C1-4alkyl or halo;
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively; and
R9 is hydrogen, methyl or ethyl.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl; and
R4 and R5 together form pyrrolidine or piperidine.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 and R5 together form pyrrolidine or piperidine; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R4 and R5 together form pyrrolidine or piperidine; and
R7 and R8 are both hydrogen
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 and R5 together form pyrrolidine or piperidine; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R4 and R5 together form pyrrolidine or piperidine; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R3 is hydroxy.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydroxy; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydroxy; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is a direct bond;
G is C1-4alkyl; and
H is hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is a direct bond;
G is C1-4alkyl;
H is hydrogen; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is a direct bond;
G is C1-4alkyl;
H is hydrogen; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring, or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R4 is C1-4alkyl; and
R5 is phenyl.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 is C1-4alkyl;
R5 is phenyl; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R4 is C1-4alkyl;
R5 is phenyl; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R4 is C1-4alkyl;
R5 is phenyl; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R4 is C1-4alkyl;
R5 is phenyl; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R6 is halo, preferably fluoro.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R6 is halo, preferably fluoro; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R6 is halo, preferably fluoro; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is hydrogen halo, hydroxy, or C1-4alkoxy;
R6 is halo, preferably fluoro; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
R6 is halo, preferably fluoro; and
R7 and R8 are joined either via a sulphur atom, via xe2x80x94C2H2xe2x80x94 or via xe2x80x94CH4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is 
G is C1-4alkyl; and
H is phenyl.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is 
G is C1-4alkyl;
H is phenyl; and
R7 and R8 are both hydrogen.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen or halo or NNxe2x80x94C1-4alkylcarbamoyl;
R2 is hydrogen;
R3 is a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H;
E is 
F is 
G is C1-4alkyl;
H is phenyl; and
R7 and R8 arc joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively.
A further preferred group of compounds of the invention include a compound of Formula VIII wherein:
R1 is selected from hydrogen or NN-di-C1-4alkylcarbamoyl;
D is selected from C1-4alkylene or C1-4alkenylene;
R2 is hydrogen;
R3 is selected from hydrogen, hydroxyl, C1-4alkoxy or a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H.
R4 and R5 each represent C1-4alkyl, R4 represents C1-4alkyl and R5 represents phenyl or together R4 and R5 form a pyrrolidino ring;
R6 is selected from hydrogen, C1-4alkyl or halo;
R7 and R8 are either both hydrogen or when A is of Formula X may be joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring or an eight membered ring respectively;
R9 is hydrogen or C1-4alkyl; and
R10 is hydrogen.
or a pharmaceutically acceptable salt, prodrug or solvate thereof.
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is selected from C1-4alkylene or C1-4alkenylene, preferably C1-2alkylene or C1-3alkenylene, most preferably ethylene or 2-propenylene;
R2 is hydrogen;
R3 is selected from hydrogen, hydroxyl, C1-4alkoxy or a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H. Preferably hydrogen, hydroxyl or C1-4alkoxy. Most preferably hydrogen or hydroxy;
R4 and R5 each represent C1-4alkyl, R4 represents C1-4alkyl and R5 represents phenyl or together R4 and R5 form a pyrrolidino ring. Preferably R4 and R5 each represent methyl or ethyl. R4 represents C1-2alkyl and R5 represents phenyl or together R4 and R5 form a pyrrolidino ring. Most preferably R4 and R5 each represent methyl or ethyl or together R4 and R5 form a pyrrolidino ring;
R6 is selected from hydrogen C1-4alkyl or halo. More preferably R6 is hydrogen, C1-2alkyl or halo. Most preferably R6 is hydrogen, methyl, ethyl or fluoro;
R7 is hydrogen;
R8 is hydrogen;
R9 is hydrogen; and
R10 is hydrogen.
or a pharmaceutically acceptable salt, prodrug or solvate thereof
A further preferred group of compounds for any feature of the invention include a compound of formula VIII wherein:
R1 is hydrogen;
D is selected from C1-4alkylene or C1-4alkenylene, preferably C1-2alkylene or C1-3alkenylene, most preferably ethylene or 2-propenylene;
R2 is hydrogen;
R3 is selected from hydrogen, hydroxyl, C1-4alkoxy or a group of the formula xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H. Preferably hydrogen, hydroxyl or C1-4alkoxy. Most preferably hydrogen or hydroxy;
R4 and R5 each represent C1-4alkyl, R4 represents C1-4alkyl and R5 represents phenyl or together R4 and R5 form a pyrrolidino ring. Preferably R4 and R5 each represent methyl or ethyl. R4 represents C1-2alkyl and R5 represents phenyl or together R4 and R5 form a pyrrolidino ring. Most preferably R4 and R5 each represent methyl or ethyl or together R4 and R5 form a pyrrolidino ring;
R6 is selected from hydrogen C1-4alkyl or halo. More preferably R6 is hydrogen, C1-2alkyl or halo. Most preferably R6 is hydrogen, methyl, ethyl or fluoro;
R7 is hydrogen;
R8 is hydrogen;
R9 is hydrogen; and
R10 is hydrogen.
With the proviso that when D is C1-4alkyl then R3 or R6 must be other than hydrogen, or R4 and R5 must be other than each independently C1-4alkyl.
or a pharmaceutically acceptable salt, prodrug or solvate thereof
Preferred compounds for any feature of the invention include: tamoxifen (preferably in the form of tamoxifen citrate), droloxifene, toremifene, idoxifene and TAT 59 (miproxifene).
Further preferred compounds for any feature of the invention include:
(1) 4-[2-(3-chlorophenyl)-1-[4-[2-(dimethylamino)ethoxy]phenyl]-1-butenyl]-Phenol;
(2) 2-[p-[1,2-bis(p-chlorophenyl)-1-butenyl]phenoxy]-N,N-dimethyl-Ethylamine;
(3) 2-[(6-ethyl-11,12-dihydro-5-phenyldibenzo[a,e]cycloocten-2-yl)oxy]-N,N-dimethyl-Ethanamine;
(4) 4-[2-[2-(dimethylamino)ethoxy]-6-ethyl-11,12-dihydrodibenzo[a,e]cycloocten-5-yl-Phenol;
(5) 2-[(10-ethyl-11-phenyldibenzo[b,f]thiepin-3-yl)oxy]-N,N-dimethyl-, Ethanamine;
(6) 4-[7-[2-(dimethylamino)ethoxy]-11-ethlydibenzo[b,f]thiepin-10-yl]-, Phenol;
(7) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]-, 1,2-Benzenediol;
(8) 2-[4-[(1Z)-4-chloro-1,2-diphenyl-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine;
(9) 2-[4-[1-(4-fluorophenyl)-2-phenyl-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine;
(10) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl, Benzeneacetic acid ester;
(11) methoxy-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Acetic acid;
(12) propyl-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Carbamic acid;
(13) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]-Phenol phenylcarbamate (ester)
(14) 4-bromo-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Benzoic acid;
(15) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]-,Phenol, benzoate (ester);
(16) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]-Phenol acetate (ester);
(17) 2-[4-(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethyl-Ethanamine;
(18) 1-[2-[4-(1,2-diphenyl-1-butenyl)phenoxy]ethyl]-Piperidine and
(19) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, 2,4,6-Trimethyl-benzoic acid.
More further preferred compounds for any feature of the invention include:
(21) 4-[2-phenyl-1-[4-[2-(1-pyrrolidinyl)ethoxy]phenyl]-1-butenyl]-, Phenol;
(22) 2,2-dimethyl-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Propanoic acid;
(23) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]-, Phenol;
(24) 1-[2-[p-[.beta.-ethyl-.alpha.-(p-methoxyphenyl)styryl]phenoxy]ethyl]-, Pyrrolidine;
(26) 2-[p-(1,2,3-triphenylpropenyl)phenoxy]-, Triethylamine;
(27) 2-[4-[1-(2-ethylphenyl)-2-phenyl-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine;
(28) 2-[(10-(NN-diethylpropanamido)-11-phenyldibenzo[b,f]thiepin-3-yl)oxy]-N,N-dimethyl-Ethanamine;
(29) 2-[4-(1,2-diphenyl-1-butenyl)phenoxy]-N-methyl-N-phenyl-, Ethanamine;
(30) 2-[4-[1-phenyl-2-(4-fluorophenyl)-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine;
(31) 3-amino-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Benzoic acid;
(32) 1-benzyl 4-[4-(1-4-[2-(dimethylamino)ethoxy]phenyl-2-phenyl-1-butenyl)phenyl]tetrahydro-1,4(2H)-pyridinedicarboxylate; and
(33) 4-(1-4-[2-(dimethylamino)ethoxy]phenyl-2-phenyl-1-butenyl)phenyl 2-[(benzyloxy)carbonyl]aminoacetate.
Most preferred compounds for any feature of the invention include:
(20) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-(4-ethylphenyl)-1-butenyl]-, Phenol;
(25) 2-[p-(1,2-diphenyl-1,4-pentadienyl)phenoxy]-Triethylamine;
Compounds for use in any feature of the invention can exist in both the (E)- and (Z)-isomeric configuration related to the proximity of groups across the double bond in compounds of Formula I and Formula VIII. Compounds of the invention are active in both their (E)- and (Z)-configurations. Preferred orientations in the numbered compounds above are:
(Z)- (1), (12), (13), (14), (17), (19), (20), (23), (26), (27), (29), (31);
(E)- (7), (8), (9), (10), (11), (15), (16), (18), (21), (22), (24), (25), (30), (32), (33).
According to another aspect of the invention there is provided a compound selected from:
(34) 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, 2,4,6-Trimethyl-benzoic acid
(35) 2-[4-[1-(2-ethylphenyl)-2-phenyl-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine
(36) 2-[(10-(NN-diethylpropanamido)-11-phenyldibenzo[b,f]thiepin-3-yl)oxy]-N,N-dimethyl-Ethanamine
(37) [4-(1,2-diphenyl-1-butenyl)phenoxy]-N-methyl-N-phenyl-, Ethanamine
(38) [4-[1-phenyl-2-(4-fluorophenyl)-1-butenyl]phenoxy]-N,N-dimethyl-, Ethanamine
(39) 3-amino-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl ester, Benzoic acid
(40) 1-benzyl 4-[4-(1-4-[2-(dimethylamino)ethoxy]phenyl-2-phenyl-1-butenyl)phenyl]tetrahydro-1,4(2H)-pyridinedicarboxylate
(41) (1-4-[2-(dimethylamino)ethoxy]phenyl-2-phenyl-1-butenyl)phenyl 2-[(benzyloxy)carbonyl]aminoacetate
or salts, prodrugs or solvates thereof
Preferred orientations in the numbered compounds of this further aspect of the invention above are:
(Z)- (34), (35), (37), (39);
(E)- (38), (40), (41).
According to another feature of the invention there is provided a pharmaceutical composition comprising a compound of the invention or a pharmaceutically acceptable salt, prodrug or solvate thereof, in association with a pharmaceutically acceptable excipient or carrier.
According to a further aspect of the present invention there is provided a method of treating or preventing cognitive disorders, such as Alzheimer""s disease, vascular dementia and age-related dementia, in a warm-blooded mammal, such as man, which comprises administering an effective amount of a compound of the invention described herein or a pharmaceutically acceptable salt, prodrug or solvate thereof.
In a further feature of the invention there is provided a method of treating or preventing Alzheimer""s disease or vascular dementia in a warm blooded mammal, such as man, which comprises administering an effective amount of a compound of the invention described herein or a pharmaceutically acceptable salt, prodrug or solvate thereof.
In a further feature of the invention there is provided a method of preventing or inhibiting ischemia-induced neurodegeneration in a warm-blooded mammal which comprises administering a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof.
In a further feature of the invention there is provided a method of preventing or inhibiting the formation of xcex2-amyloid plaques or neurofibrillary tangles in the brain in a warm-blooded mammal comprising administering an effective amount of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof.
In a further feature of the invention there is provided a method of inhibiting or preventing the inflammatory response associated with Alzheimer""s Disease in a warm blooded mammal comprising administering an effective amount of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof.
In a further feature of the invention there is provided a method of treating stroke, head trauma or spinal cord injury in a warm blooded mammal comprising administering an effective amount of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the treatment of neurological disorders in a warm blooded mammal.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the treatment of cognitive disorders, such as Alzheimer""s disease, vascular dementia or age-related dementia in a warm blooded mammal.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the prevention of or the inhibition of ischemia-induced neurodegeneration in a warm blooded mammal.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the prevention of or the inhibition of the formation of xcex2-amyloid plaques or neurofibrillary tangles in the brain in a warm blooded mammal.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the prevention of or the inhibition of the inflammatory response associated with Alzheimer""s Disease in a warm blooded mammal.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the treatment of stroke, head trauma or spinal cord injury.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the prevention or treatment of neurological disorders in a warm blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the prevention or treatment of cognitive disorders, such as Alzheimer""s disease, vascular dementia or age-related dementia in a warm blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the prevention of or the inhibition of ischemia-induced neurodegeneration in a warm-blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the prevention of or the inhibition of the formation of xcex2-amyloid plaques or neurofibrillary tangles in the brain in a warm blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the prevention of or the inhibition of the inflammatory response associated with Alzheimer""s Disease in a warm blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein, or a pharmaceutically acceptable salt, prodrug or solvate thereof, in admixture with a pharmaceutically-acceptable diluent or carrier for the treatment of stroke, head trauma or spinal cord injury.
According to a further feature of the current invention there is provided a method of treating or preventing neuronal apoptosis and/or excitotoxicity related neurological disorders in a warm-blooded mammal which comprises administering to said warm-blooded mammal an effective amount of a compound of the invention described herein or a pharmaceutically acceptable salt, prodrug or solvate thereof.
According to a further feature of the current invention there is provided the use of a compound of the invention described herein or a pharmaceutically acceptable salt, prodrug or solvate thereof, for the manufacture of a medicament for the treatment or prevention of neuronal apoptosis and/or excitotoxicity related neurological disorders in a warm blooded mammal.
According to a further feature of the current invention there is provided a pharmaceutical composition comprising a compound of the invention described herein or a pharmaceutically acceptable salt, prodrug or solvate thereof for the prevention or treatment of neuronal apoptosis and/or excitotoxicity related neurological disorders in a warm blooded mammal.
According to a further feature of the invention there is provided the use of a compound, which has a high affinity for the emopamil binding protein and inhibits neuronal apoptosis and/or neuronal excitotoxicity, for the treatment or prevention of neurological disorders.
According to a further feature of the invention there is provided the use of a compound, which has a high affinity for the emopamil binding protein and inhibits neuronal apoptosis, for the treatment or prevention of neurological disorders.
According to a further feature of the invention there is provided the use of a compound, which has a high affinity for the emopamil binding protein and inhibits neuronal excitotoxicity, for the treatment or prevention of neurological disorders.
The methods of treatment, compositions or medicaments may be used to treat patients who exhibit neurological disorders in order to at least ameliorate symptoms of such disorders and/or to treat patients prophylactically to prevent or inhibit onset of neurological disorders in patients who have a susceptibility to developing such disorders.
The expression xe2x80x9cneurological disordersxe2x80x9d includes to cognitive disorders, neuronal apoptosis, excitotoxicity and/or disorders which comprise neuronal apoptosis and/or excitotoxicity as part of their pathology.
Such xe2x80x9cneurological disorders include, but are not limited to, Alzheimer""s disease, vascular dementia and age-related dementia as well as head trauma, stroke, spinal cord injury, amyotrophic lateral sclerosis (ALS), Parkinson""s disease, Huntington""s chorea, AIDS-related dementia, peripheral neuropathies and macular degeneration.
The expression xe2x80x9cneuronal apoptosis and/or excitotoxicity related neurological disordersxe2x80x9d as used herein means neurological disorders in which either neuronal apoptosis or excitotoxicity are implicated as a pathological process in said neurological disorders or both neuronal apoptosis and excitotoxicity are implicated as a pathological process in said neurological disorders.
The term xe2x80x98tamoxifenxe2x80x99 as used herein includes tamoxifen and it is physiologically compatible salts, but is preferably used to refer to tamoxifen citrate.
The term cognitive disorder means any disturbance of normal function related to the mental activities associated with thinking, learning and memory, or any process whereby one acquires knowledge.
The term xe2x80x9cinhibitxe2x80x9d includes its generally accepted meaning which includes prohibiting, preventing, restraining, and slowing, stopping, or reversing progression, severity, or a resultant symptom or effect.
The term xe2x80x9ceffective amountxe2x80x9d means the amount of compound necessary to inhibit or prevent a cognitive disorder such as Alzheimer""s Disease or any of its symptoms, inhibit of prevent ischemia-induced neurodegeneration, inhibit or prevent beta -amyloid peptide mediated neurotoxicity or inhibit or prevent the inflammatory response associated with Alzheimer""s Disease, as the case may be.
Generally, the compound is formulated with common excipients, diluents or carriers, and compressed into tablets, or formulated as elixirs or solutions for convenient oral administration, or administered by the intramuscular or intravenous routes. The compounds can be administered transdermally, and may be formulated as sustained release dosage forms and the like.
Processes for producing the preferred compounds of the invention and other tamoxifen analogues are detailed in the following patents: toremifene (U.S. Pat. No. 5,491,173, U.S. Pat. No. 4,996,225), droloxifene (U.S. Pat. No. 5,047,431), TAT 59 (U.S. Pat. No. 4,897,503) and idoxifene (U.S. Pat. No. 4,839,155), each incorporated by reference herein.
The compounds used in the methods of the current invention, wherein both R7 and R8 are both hydrogen, are made according to the general procedures as follows: Briefly the starting compound of Formula II, 
wherein R1xe2x80x2 is hydrogen, D and R6 are as described above, is demethylated with a boron trihalide at between 0xc2x0 C. and room temperature, typically using methylene chloride as solvent. The product of this reaction is then reacted with a compound of the general formula:
R4R5Nxe2x80x94[CH2]nCl
wherein R4, R5 and n are as described above, conveniently in the presence of a base, to give a compound of formula III: 
The compound of Formula III is further reacted by a Grignard reaction in an inert solvent with a phenylmagnesiumhalide derivative of the formula: 
or with a organometallic halobenzene species of the formula: 
in which R2 is hydrogen, C1-4alkyl or a protected hydroxyl group and R3, is either hydrogen, a protected hydroxyl, alkoxy or halo, to produce a compound of Formula IV: 
The hydroxyl protecting group could typically be tetrahydopyranyl (thp). The compound of Formula IV is then dehydrated using an appropriate acid catalyst, for example hydrochloric acid, in an appropriate solvent, for example ethanol, to produce a mixture of cis and trans isomers which can be separated by fractional crystallization or chromatography to yield the cis or trans isomer of Formula I or Formula VIII. Under the dehydration conditions the thp protecting group will also be removed.
For the formation of compounds used in the methods of the invention wherein R7 and R8 are joined either via a sulphur atom, via xe2x80x94CH2xe2x80x94 or via xe2x80x94C2H4xe2x80x94 to form a seven membered sulphur-containing ring, a seven-membered ring, or an eight membered ring respectively and A is of Formula X, a compound of Formula XI is used. 
wherein R1xe2x80x2 is hydrogen, J is a group of the formula, xe2x80x94Sxe2x80x94, xe2x80x94CH2xe2x80x94 or xe2x80x94CH2CH2xe2x80x94 and D and R6 are as defined above. For the synthesis of a compound of Formula XI the reader is referred to Acton et al [1983] J. Med Chem. 26, 1131-1137.
A compound of formula XI may be de-methylated as described above and then reacted with a compounds of the general formula:
R4R5Nxe2x80x94[CH2]nCl
to form a compound of Formula XII. 
The compound of Formula XII is further reacted by a Grignard reaction in an inert solvent with a phenylmagnesiumhalide derivative of the formula: 
or with a organometallic halobenzene species of the formula: 
in which R2, is hydrogen, C1-4alkyl or a protected hydroxyl group and R3, is either hydrogen, a protected hydroxyl or halo, to produce a compound of Formula XIII: 
A analogous series of reactions can be used to synthesise compounds of the invention wherein Formula X is of the Formula Xa. 
For the formation of compounds of the invention which have a PO4 group at R3, R3, is a protected hydroxyl group. At the end of the synthesis, after the deydration step and separation of the cis isomer of Formula I, the hydroxyl group is phosphorylated. Usable as phosphorylating groups are, for example, phosphorous oxyhalides such as phosphorous oxychloride and phosporous oxychloride, phosphoric acid anhydrides such as pyrophosphonic acid and polyphosphoric acid. Among these preferred is phosphorous oxychloride. A suitable solvent for this reaction in one which activates the phosphorylating group and does not interfere with the reaction. Suitable solvents include pyridine, tetrahydrofuran and acetonitrile. For information relating the phosphorylation conditions the reader is referred to U.S. Pat. No. 4,897,503.
For the formation of compounds used in the methods of the invention wherein R3 is of the formula:
xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H
and E is selected from: 
a compound of Formula I or Formula VIII wherein R3 is a hydroxyl may be acylated with an acylating derivative obtained from an acid of the formula:
HOOCxe2x80x94Exe2x80x2xe2x80x94Fxe2x80x94Gxe2x80x94H
wherein E is the group E without the oxygen and carboxyl on the left of the group or when E is a group of the formula: 
may be reacted with an isocyanate of the formula:
OCNxe2x80x94Fxe2x80x94Gxe2x80x94H
Compounds used in the methods of the invention wherein R3 is of the formula:
xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H
and E is selected from: 
can be made from a compound of Formula XIV wherein the A, B, D, R2, R4, R5, R8 and R9 are as in herein before defined. 
A chemist skilled in the art would be able to synthesise the respective acid or isocyanate derivatives of the group xe2x80x94Exe2x80x94Fxe2x80x94Gxe2x80x94H to be used in coupling to a compound of Formula I or Formula VIII wherein R3 is a hydroxyl.
Compounds used in methods of the invention wherein R1 is halo can be prepared from a compound of Formula XV or the corresponding derivative of Formula XI, wherein R6 and R10 are as herein before defined and R11 is a protecting group. 
to form the corresponding compound of Formula I or Formula VIII wherein R1 is hydroxyl. This can then be converted by various methods to a compound of Formula I or Formula VIII wherein R1 is halo.
Compounds used in methods of the invention wherein R1 is, carbamoyl, Nxe2x80x94C1-4alkylcarbamoyl or NN-di-C1-4alkylcarbamoyl can be prepared from the appropriate carboxylic acid using ammonia, or the appropriate primary or secondary amine.
The reader is referred to Protective Groups in Organic synthesis, 2nd Edition, by Green et al., published by John Wiley and Sons for general guidance on protecting groups.
Specifically tamoxifen can be produced as detailed in U.S. Pat. No. 4,536,516. Briefly the process starts with (xcex1-ethyl-4-methoxydesoxybenzoin which is demethylated with pyridine hydrochloride at high temperature to give 4-hydroxy-xcex1-ethyldesoxybenzoin. The sodium salt of the latter compound is then reacted with xcex2-dimethylaminoethyl chloride to form a compound of Formula V: 
Formula II is then reacted with the Grignard reagent, phenyl magnesium bromide in an inert solvent to give a compound of formula VI. 
Dehydration of the alkanol of Formula III is then carried out via reaction with an acid catalyst, for example hydrochloric acid, in a solvent for example ethanol with the application of heat. The dehydration of formula III yields a mixture of cis and trans isomers which can be separated by fractional crystallization to give the cis isomer of formula I.
Alternative methods for the production of Formula VII can be found in U.S. Pat. No. 4,960,937, incorporated by reference herein where R2 is as defined above. 
The present invention relates to the compounds of Formula I or Formula VIII as hereinbefore defined as well as to the salts thereof. Salts for use in pharmaceutical compositions will be pharmaceutically acceptable salts, but other salts may be useful in the production of the compounds of formula I and their pharmaceutically acceptable salts. A suitable pharmaceutically-acceptable salt of a compound of the Formula I or Formula VIII is, for example, an acid-addition salt of a compound of the Formula I or Formula VIII which is sufficiently basic, for example an acid-addition salt with an inorganic or organic acid such as hydrochloric, hydrobromic, sulphuric, trifluoroacetic, citric or maleic acid; or, for example a salt of a compound of the Formula 1 or Formula VIII which is sufficiently acidic, for example an alkali or alkaline earth metal salt such as a calcium or magnesium salt, or an ammonium salt, or a salt with an organic base such as methylamine, dimethylamine, trimethylamine, piperidine, morpholine or tris-(2-hydroxyethyl)amine.
Various forms of prodrugs are known in the art. For examples of such prodrug derivatives, see:
a) Design of Prodrugs, edited by H. Bundgaard, (Elsevier, 1985) and Methods in Enzymology, Vol.42, p. 309-396, edited by K. Widder, et al. (Academic Press, 1985);
b) A Textbook of Drug Design and Development, edited by Krogsgaard-Larsen and H. Bundgaard, Chapter 5 xe2x80x9cDesign and Application of Prodrugsxe2x80x9d, by H. Bundgaard p. 113-191 (1991);
c) H. Bundgaard, Advanced Drug Delivery Reviews, 8, 1-38 (1992);
d) H. Bundgaard, et al., Journal of Pharmaceutical Sciences, 77, 285 (1988); and
e) N. Kakeya, et al., Chem Pharm Bull, 32, 692 (1984).
Examples of such pro-drugs may be used to form in vivo cleavable esters of a compound of the Formula (1). An in vivo cleavable ester of a compound of the Formula (1) containing a carboxy group is, for example, a pharmaceutically-acceptable ester which is cleaved in the human or animal body to produce the parent acid. Suitable pharmaceutically-acceptable esters for carboxy include C1-6alkoxymethyl esters, for example methoxymethyl; C1-6alkanoyloxymethyl esters, for example pivaloyloxymethyl; phthalidyl esters; C3-8cycloalkoxycarbonyloxyC1-6alkyl esters, for example 1-cyclohexylcarbonyloxyethyl; 1,3-dioxolan-2-ylmethyl esters, for example 5-methyl-1,3-dioxolan-2-ylmethyl; and C1-6alkoxycarbonyloxyethyl esters, for example 1-methoxycarbonyloxyethyl; and may be formed at any carboxy group in the compounds of this invention.
It will also be understood that certain compounds of the present invention may exist in solvated, for example hydrated, as well as unsolvated forms. It is to be understood that the present invention encompasses all such solvated forms which possess the properties of inhibiting or preventing cognitive disorders, inhibiting or preventing ischemia-induced neurodegeneration, inhibiting or preventing the formation of xcex2-amyloid plaques or neurofibrillary tangles in the brain, or inhibiting or preventing the inflammatory response associated with Alzheimer""s.
The compositions of the invention may be in a form suitable for oral use (for example as tablets, lozenges, hard or soft capsules, aqueous or oily suspensions, emulsions, dispersible powders or granules, syrups or elixirs), for topical use (for example as creams, ointments, gels, or aqueous or oily solutions or suspensions), for administration by inhalation (for example as a finely divided powder or a liquid aerosol), for administration by insufflation (for example as a finely divided powder) or for parenteral administration (for example as a sterile aqueous or oily solution for intravenous, subcutaneous, intramuscular or intramuscular dosing or as a suppository for rectal dosing).
The compositions of the invention may be obtained by conventional procedures using conventional pharmaceutical excipients, well known in the art. Thus, compositions intended for oral use may contain, for example, one or more colouring, sweetening, flavouring and/or preservative agents.
Suitable pharmaceutically-acceptable excipients for a tablet formulation include, for example, inert diluents such as lactose, sodium carbonate, calcium phosphate or calcium carbonate, granulating and disintegrating agents such as corn starch or algenic acid; binding agents such as starch; lubricating agents such as magnesium stearate, stearic acid or talc; preservative agents such as ethyl or propyl p-hydroxybenzoate, and anti-oxidants, such as ascorbic acid. Tablet formulations may be uncoated or coated either to modify their disintegration and the subsequent absorption of the active ingredient within the gastrointestinal tract, or to improve their stability and/or appearance, in either case, using conventional coating agents and procedures well known in the art.
Compositions for oral use may be in the form of hard gelatin capsules in which the active ingredient is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules in which the active ingredient is mixed with water or an oil such as peanut oil, liquid paraffin, or olive oil.
Aqueous suspensions generally contain the active ingredient in finely powdered form together with one or more suspending agents, such as sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinyl-pyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents such as lecithin or condensation products of an alkylene oxide with fatty acids (for example polyoxethylene stearate), or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives (such as ethyl or propyl p-hydroxybenzoate, anti-oxidants (such as ascorbic acid), colouring agents, flavouring agents, and/or sweetening agents (such as sucrose, saccharine or aspartame).
Oily suspensions may be formulated by suspending the active ingredient in a vegetable oil (such as arachis oil, olive oil, sesame oil or coconut oil) or in a mineral oil (such as liquid paraffin). The oily suspensions may also contain a thickening agent such as beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set out above, and flavouring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an anti-oxidant such as ascorbic acid.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water generally contain the active ingredient together with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients such as sweetening, flavouring and colouring agents, may also be present.
The pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, such as olive oil or arachis oil, or a mineral oil, such as for example liquid paraffin or a mixture of any of these. Suitable emulsifying agents may be, for example, naturally-occurring gums such as gum acacia or gum tragacanth, naturally-occurring phosphatides such as soya bean, lecithin, an esters or partial esters derived from fatty acids and hexitol anhydrides (for example sorbitan monooleate) and condensation products of the said partial esters with ethylene oxide such as polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening, flavouring and preservative agents.
Syrups and elixirs may be formulated with sweetening agents such as glycerol, propylene glycol, sorbitol, aspartame or sucrose, and may also contain a demulcent, preservative, flavouring and/or colouring agent.
The pharmaceutical compositions may also be in the form of a sterile injectable aqueous or oily suspension, which may be formulated according to known procedures using one or more of the appropriate dispersing or wetting agents and suspending agents, which have been mentioned above. A sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example a solution in 1,3-butanediol.
Suppository formulations may be prepared by mixing the active ingredient with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Suitable excipients include, for example, cocoa butter and polyethylene glycols.
Topical formulations, such as creams, ointments, gels and aqueous or oily solutions or suspensions, may generally be obtained by formulating an active ingredient with a conventional, topically acceptable, vehicle or diluent using conventional procedures well known in the art.
Compositions for administration by insufflation may be in the form of a finely divided powder containing particles of average diameter of, for example, 30 xcexcm or much less, the powder itself comprising either active ingredient alone or diluted with one or more physiologically acceptable carriers such as lactose. The powder for insufflation is then conveniently retained in a capsule containing, for example, 1 to 50 mg of active ingredient for use with a turbo-inhaler device, such as is used for insufflation of the known agent sodium cromoglycate.
Compositions for administration by inhalation may be in the form of a conventional pressurised aerosol arranged to dispense the active ingredient either as an aerosol containing finely divided solid or liquid droplets. Conventional aerosol propellants such as volatile fluorinated hydrocarbons or hydrocarbons may be used and the aerosol device is conveniently arranged to dispense a metered quantity of active ingredient.
Frequently, it will be desirable or necessary to introduce the pharmaceutical compositions directly or indirectly to the brain. Direct techniques usually involve placement of a drug delivery catheter into the host""s ventricular system to bypass the blood-brain barrier. Indirect techniques, which are generally preferred, involve formulating the compositions to provide for drug latentiation by the conversion of hydrophilic drugs into lipid-soluble drugs. Latentiation is generally achieved through blocking of the hydroxyl, carboxyl, and primary amine groups present on the drug to render the drug more lipid soluble and amenable to transportation across the blood-brain barrier. Alternatively, the delivery of hydrophilic drugs can be enhanced by intra-arterial infusion of hypertonic solutions which can transiently open the blood-brain barrier.
For further information on Formulation the reader is referred to Chapter 25.2 in Volume 5 of Comprehensive Medicinal Chemistry (Corwin Hansch; Chairman of Editorial Board), Pergamon Press 1990.
The amount of active ingredient that is combined with one or more excipients to produce a single dosage form will necessarily vary depending upon the host treated and the particular route of administration. For example, a formulation intended for oral administration to humans will generally contain, for example, from 0.5 mg to 2 g of active agent compounded with an appropriate and convenient amount of excipients which may vary from about 5 to about 98 percent by weight of the total composition. Dosage unit forms will generally contain about 1 mg to about 500 mg of an active ingredient. For further information on Routes of Administration and Dosage Regimes the reader is referred to Chapter 25.3 in Volume 5 of Comprehensive Medicinal Chemistry (Corwin Hansch; Chairman of Editorial Board), Pergamon Press 1990.
The size of the dose for therapeutic or prophylactic purposes of a compound of the Formula I or Formula VIII will naturally vary according to the nature and severity of the conditions, the age and sex of the animal or patient and the route of administration, according to well known principles of medicine.
In using a compound of the Formula I or Formula VIII for therapeutic or prophylactic purposes it will generally be administered so that a daily dose in the range, for example, 0.1 mg to 1000 mg per day is received, given if required in divided doses. In general lower doses will be administered when a parenteral route is employed. Thus, for example, for intravenous administration, a dose in the range, for example, 0.5 mg to 30 mg per kg body weight will generally be used. Similarly, for administration by inhalation, a dose in the range, for example, 0.5 mg to 25 mg per kg body weight will be used. Oral administration is however preferred, particularly in tablet form. The unit dosage forms will contain about 1 mg to 500 mg of a compound of this invention, more typically the dosage form would contain between 1 mg and 50 mg. Compounds of Formula I or Formula VIII are preferably administered orally, conveniently in a dosage of 10-40 mg daily.
The compounds of this invention may be used in combination with other drugs and therapies used in the treatment or prevention of cognitive disorders such as Alzheimer""s disease, vascular dementia or, less preferably, age-related dementia.
If formulated as a fixed dose such combination products employ the compounds of this invention within the dosage range described herein and the other pharmaceutically-active agent within its approved dosage range. Sequential use is contemplated when a combination formulation is inappropriate.
The invention will now be illustrated with reference to the following non-limiting examples.
The displacement of 3H-emopamil binding assay, the NMDA-induced neuronal dealth model and the inhibition of apoptosis in PC12 cells are all standard assays/models recognised in the medical community as indicative of efficacy.
Compounds that bind with high affinity to the 3H-emopamil binding protein have been shown to be neuroprotective in animal models of cerebral ischemia. As the emopamil binding protein has been shown to be the mammalian homolog of delta-8, delta-7 sterol isomerase, it has been suggested that the neuroprotective mechanism of high affinity 3H-emopamil binding site ligands results from the inhibition of de novo cholesterol metabolism. Inhibition of cholesterol metabolism may alter the processing of amyloid precursor protein in a manner that would be expected to delay the progression of Alzheimer""s disease pathophysiology. Therefore, high affinty 3H-emopamil binding site ligands that inhibit the de novo synthesis of cholesterol would be expected to alleviate ischemia induced neurodegeneration and inhibit the pathophysiological progression of Alzheimer""s disease. [See: Moebius et al., Trends Pharmacol Sci 18:67-70, 1997; Racchi et al., Biochem J 322:893-898, 1997; Silve et al., Mol. Cell. Biol. 16:2719-2727, 1996].
NMDA-induced neuronal death is a model of excitotoxicity that is reflective of death induced by necrosis. During cerebral ischemic events there is excessive release of glutamate, the endogenous NMDA receptor agonist, that results in neuronal cell death due predominantly to necrotic mechanisms. Compounds that inhibit NMDA receptor function are active in experimental models of ischemia that are thought to be most reflective of the clinical situation, and a number of these compounds are in clinical trial evaluation for the treatment of stroke. Recurrent ischemic events are the proximal cause of dementia in vascular dementia, and ischemia-induced neurodegeneration severely exacerbates the cognitive decline that is associated with Alzheimer""s disease pathphysiology. Therefore, drugs that inhibit NMDA receptor function would be expected to preserve neurons in stroke, and prevent ischemia induced cognitive decline that is observed in vascular dementia and Alzheimer""s disease. [See: Gotti et al., Brain Research 522:290-307, 1990; Gwag et al., Neuroscience 68:615-619, 1995; Koroshetz and Moskowitz, Trends in Pharmacological Sci. 17:227-233, 1996;
Snowdon et al., JAMA, 277:813-817, 1997].
Nerve growth factor withdrawal in differentiated PC12 cells is a model of neuronal death induced by apoptosis. Neurodegeneration resulting from apoptotic mechanisms has been implicated in a number of disease processes, including stroke, traumatic brain injury, Alzheimer""s disease, Parkinson""s disease, amyotrophic lateral sclerosis, vascular dementia, AIDS related dementia and macular degeneration. Therefore, compounds that are active in inhibiting, apoptosis in PC12 cells would be expected to alleviate the neuronal death associated with apoptosis in these neurological disorders [See: Barinaga, Science 281:1303-1304, 1998;
Kusiak et al., Molecular and Chemical Neuropathology 28:153-162, 1996; Spence et al., Exp. Opin. Ther. Patents 6:345-366, 1996; Charriaut-Marlangue et al., TINS 19:109-114, 1996; von Bartheld, Histology and Histopathology, 13:437-459, 1998; Hara et al., Proc. Natl. Acad. Sci., USA 94:2007-2012, 1997; Yakovlev, et al., J. Neuroscience 17:7415-7424, 1997].
Neuronal cell death in stroke, Alzheimer""s disease, Parkinson""s disease and other neurological disorders is believed to occur as a result of pathophysiological mechanisms associated with both apoptosis and necrosis, and may depend on the severity of neuronal insult. While pharmacological approaches that inhibit either necrosis or apoptosis would be expected to offer some benefit, this benefit may be limited due to incomplete inhibition of the pathways that lead to neuronal cell death. For example, neurotrophic factors that inhibit neuronal apoptosis exacerbate excitotoxicity induced by NMDA receptor activation. It is thus possible that preventing apoptosis may ultimately result in increased necrotic cell death. Optimal neuroprotective approaches may therefore be those that can inhibit both apoptosis and necrosis. In this regard, compounds of Formula I or Formula VIII, especially tamoxifen citrate, has have been shown to inhibit both apoptosis and necrosis, and therefore greater therapeutic benefit than approaches that only inhibit one path to neuronal cell death, eg, inhibitors of NMDA receptors that only inhibit necrosis, or neurotrophic factors that only inhibit apoptosis. [See: Ferrer et al., Acta Neuropathol. (Ber) 90:504-510, 1995; Choi, Current Opinion in Neurobiology 6:667-672, 1996; Koh et al., Science 268:573-575, 1995].
Displacement of 3H-Emopamil Binding to Guinea Pig Liver Membranes
The method of displacement of 3H-emopamil binding was a modification of Zech et al (1991) Eur. J. Pharm. 208:119-130.
The Guinea-pig liver membranes were prepared as follows: Male guinea pigs were sacrificed by CO2 asphyxiation with dry ice. The livers were quickly excised and weighed and rinsed in membrane preparation buffer containing 10 mM Hepes, 1 mM Tris base-EDTA, 250 mM sucrose, pH 7.4. The livers were then minced homogenized in 10 times volume with a motor driven Teflon-glass homogenizer with three strokes on ice. The homogenate was centrifuged at 1000xc3x97g in a SS34 rotor for 5 minutes at 4xc2x0 C. The supernatant was filtered through 4 layers of gauze and then centrifuged at 8000xc3x97g for 10 minutes 4xc2x0 C. This resulting supernatant was centrifuged at 40,000xc3x97g for 15 minutes at 4xc2x0 C. The resulting pellet was resuspended in assay buffer and centrifuged again at 40,000xc3x97g for 15 minutes at 4xc2x0 C. This pellet was resuspended in assay buffer (2.5 fold with respect to original wet weight) and homogenized with one stroke with the Teflon-glass homogenizer. Aliquots of 1 mL were stored at xe2x88x9270xc2x0 C.
The displacement assay was performed as follows: The reaction mixture contained: Assay buffer: 10 mM Tris-HCl, 0.1 mM phenylmethylsulfonyl fluoride (PMSF), 0.2% bovine serum albumin (BSA), pH 7.4 at 40xc2x0 C.
Radioligand: 0.96 nM (xe2x88x92)-3H-emopamil (Amersham).
Guinea pig liver membranes: 40 mg/mL original wet weight.
Compounds: 1-300 nM.
Total volume: 500 xcexcL.
This mixture was incubated for 60 minutes at 37xc2x0 C. The incubation was terminated by filtering with a Brandel Cell Harvester over Whatman GF/C filters that had been soaked for at least 120 minutes in 0.3% polyethylenamine (PEI) and washed three times with 5 mL of wash buffer containing 10 mM Tris-HCl, 10 mM MgCl2, 0.2% BSA, pH 7.4 at 25xc2x0 C. Specific binding was defined with 10 xcexcM emopamil. In general compounds with an IC50 below 1 xcexcM in this test were of interest.
Inhibition of NMDA-induced Death of Mouse Cortical Neurons in Primary Cell Culture
A glial feeder layer was prepared from post-natal day 1 or 2 mice. Cortices were dissected in a Ca2+/Mg2+-free balanced salt solution, minced, incubated in media stock (MS: GIBCO""s MEM supplemented with bicarbonate, glucose, and glutamine) containing trypsin for 30 minutes at 37xc2x0 C., and centrifuged at 1500 g for 5 minutes to produce a cell pellet. The pellet was re-suspended in plating media (MS supplemented with horse and fetal calf serum) and triturated with a glass pasteur pipette. Cells were plated in 24-well Falcon Primaria tissue culture dishes at a density of 0.5 hemispheres per plate. The dishes had been coated overnight with 10 mg/ml mouse laminin and 25 mg/ml poly-lysine, then washed three times with water. The glial feeder layer was maintained in a humidified atmosphere of 5% CO2/95% air at 37xc2x0 C. for two weeks.
Cortices prepared using similar methods from embryonic day 16 mice (from which only neurons survive in culture) were plated on the glial feeder layer at the end of two weeks at a density of 350,000 cells per well. Six days later, mixed glial/neuronal cultures were treated with 10 mM cytosine-arabinoside for 48 hours to prevent further mitosis, and then fed with fresh media containing 3 mM tamoxifen citrate. Media was exchanged with media containing fresh tamoxifen after three days. After six days of drug treatment, cultures were washed three times with a HEPES-buffered control salt solution (HCSS in mM: 120 NaCl, 5.4 KCl, 0.8 MgCl2, 2.6 CaCl2, 15 glucose, 20 HEPES, 10 NaOH, pH 7.4), treated with 300 xcexcM NMDA and 10 mM glycine for five minutes in HCSS, again washed three times with HCSS, and then returned to the incubator in MS. 24 hours later, samples of cell culture media were removed from each well and tested for cell death by measuring lactate dehydrogenase (LDH) activity in the growth medium.
LDH activity was measured as follows: 50 ml of cell-culture media from each well was mixed with 200 ml 0.1 M KH2PO4 containing 30 mg NADH, in a 96-well microtitre plate. After 10 minutes at room temperature, 30 ml of 2.4 mM sodium pyruvate was added, and the absorbance of this solution at 340nm was immediately measured at 15 second intervals for approximately 6 minutes using a Molecular Devices Spectromax 250 plate-reader. NADH absorbs light at 340 nm. The rate of decline in absorption at 340 nM was fitted by linear regression to derive Vmax which is a linear function of LDH concentration. Vmax data was converted to percent neuronal death by normalizing to Vmax measurements of cell-culture media from cells not exposed to NMDA (no neuronal death) and cells exposed to 300 mM NMDA for 24 hours (complete neuronal death with glial sparing),according to the formula (DVmaxxe2x88x92CVmax)(Vmaxxe2x88x92CVmax)xc3x97100, where DVmax, CVmax, NVmax, are Vmax measurements from drug-treated cultures exposed to NMDA for 5 minutes, cultures left untreated, and cultures exposed to NMDA for 24 h, respectively. Individual experiments were repeated in quadruplicate.
Inhibition of Apoptosis in PC12 Cells Induced by NGF Withdrawal
Rat PC12 cells (ATCC Accession Number CRL-1721) were grown in RPMI0-1640 buffer containing 10% heat-inactivated Fetal Bovine Serum (FBS) and 1% L-glutamine (Gibco). Cells were plated in 100 mm Collagen I Falcon plates (Becton Dickinson)at a density of xcx9c1xc3x97106-2xc3x97106 and passed every other day at 1:10 ratio (cells were trypsinized and centrifuged at 1000 rpm for 5 min. Cells were resuspended and plated at the density of 1-2xc3x97106 cells). Tamoxifen was dissolved in DMSO at a concentration of 10 mM. Subsequent dilutions were done in PC12 cell growth medium containing 1% FBS.
NGF-induced differentiation and withdrawal: PC12 cells were differentiated into a neuronal phenotype in RPMI 1640 containing 1% FBS and 50 ng/ml NGF (2.5S, Cat.#N6009, Sigma). Differentiation of PC12 cells into the neuronal phenotype (neurite extension) took 9-14 days. Nerve growth factor (NGF) withdrawal was accomplished by washing the cells once with NGF-free medium. Cells were then trypsinized, centrifuged and plated onto 96-well plates at a density of xcx9c1xc3x97104/well. This was followed by incubation in NGF-free medium containing rabbit antibody (anti-NGF) against 2.5sNGF (Sigma catalog# N6655) at a 1:400 dilution. Drugs were added immediately after NGF withdrawal. Cells were incubated with or without drug for 3 hours and harvested by trypsinization. After 3 hr, cells were spun at 1000 RPM for 10 min, the supernatant discarded. 1xc3x97106 cells were used for each assay (96 well plate),
Cells were harvested at various time points after the NGF withdrawal procedure to determine the time course of cell death. Apoptosis assays (Cell Death Detection ELISA) and cell necrosis assays (LDH) were conducted as described below. Compounds were used at various concentrations and the extent of apoptosis that occurred in the presence of compounds was expressed as a percentage relative to control cultures that were exposed to vehicle only. Thus, 100% was equivalent to no inhibition of apoptosis and 0% was equivalent to total inhibition of apoptosis.
Inhibition of Apoptosis in PC12 Cells Induced by b-amyloid
Rat PC12 cells were cultured as described above.
b-Amyloid (1-42), as a 1 mM aqueous stock solution (Bachem (Cat# H-1368)) was aggregated overnight at room temperature before use. Amyloid aggregation spontaneously occurs under these conditions. In initial experiments, a dose-response relationship was examined and it was determined that 100 nM b-Amyloid added to NGF differentiated PC12 cells (in the presence of NGF) for 3 hr resulted in apoptosis.
Cells were trypsinized, centrifuged at 1000 rpm for 5 min, and plated at 1xc3x97104 cells/well. 100 nM of aggreagted b-Amyloid was added to NGF differentiated PC12 cells. Cells were harvested by trypsinization at 3 h after the addition of b-Amyloid.
Apoptosis was measure by using Cell Death ELISA kit from Boehringer-Mannheim as described below.
Cell Death (Apoptosis) Detection ELISA for PCI 2 Cells
Cell death was measured using a Cell Death Detection ELISA (Boehringer-Mannheim Cat# 1774425) according to manufacturers instructions.The ELISA is a photometric enzyme-immunoassay which determines the amount of cytoplasmic histone-associated-DNA-fragments after induced cell death.
Cells pellets from each assay were resuspended in 200 ul lysis buffer (from kit -). The sample was placed into streptavidin-coated micotiter plate. A mixture of anti-histone-biotin and anti-DNA-peroxidase are added and incubated for an additional 2 hr. The unbound antibodies are removed by a washing step. The amount of nucleosomes is quantified by the peroxidase retained in the immunocomplex. Peroxidase was determined colorimetrically with 2,2xe2x80x2-Azino-di[3-ethylbenzthiazolin-sulfonat] (ABTS) as a substrate.
LDH Assay for Determining Necrosis in PC12 Cells
LDH was measured using a commercially available kit death (Boehringer-Mannheim; LDH Kit, Cat. # 1 644 793. A modification of procedure described by Koh and Choi, J. Neurosci. Methods 20:83-90, 1987). An alternative method is described in Example 2.
As stated above, differentiated PC12 cells (50 ng/ml NGF for 12 days) were used at 10,000 cells/well. To determine the LDH activity, 100 ul of the supernatant from the PC12 cells was added to reaction mixture which consists of solution I [catalyst] and Solution II [dye) and incubated for 30 min at RT. LDH activity was measure at 490 nm.
Although the pharmacological properties of the compounds of Formula I or Formula VIII vary with structural change as suspected, in general they have an affinity for the emopamil binding protein between 0.1 nM and 1 xcexcM and in the inhibition of apoptosis in the PC12 cells assay values between 0 and 75% were measured. For example: 2,2-dimethyl-, 4-[1-[4-[2-(dimethylamino)ethoxy]phenyl]-2-phenyl-1-butenyl]phenyl Propanoic acid ester, (E)- has an IC50 of 75 nM for the emopamil binding protein and a percentage of 41% in the PC12 assay.